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Associate Retirement Plans - Additional Information (Detail) - USD ($) $ in Millions				3 Months Ended		9 Months Ended
	Jun. 28, 2024	Jul. 01, 2023	Jun. 30, 2022	Oct. 05, 2024	Oct. 07, 2023	Oct. 05, 2024	Oct. 07, 2023
Retiree Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit (income) expense					$ 0.8	$ 1.7	$ 2.5
Increase (Decrease) in obligations			$ 6.6
SpartanNash Retiree Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit (income) expense	$ 0.1	$ 0.3			0.7	1.4	2.2
Payment to retired participants	$ 1.3	$ 1.3
Central States, Southeast and Southwest Areas Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension contributions during last plan year				$ 2.3	$ 2.3	$ 10.2	$ 10.2

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Payment To Retired Participants

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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Amount of increase (decrease) in obligation for pension and other postretirement benefits. Includes, but is not limited to, defined benefit and defined contribution plans.

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Amount of contribution received by multiemployer pension plan from all employers participating in multiemployer pension plan determined to be individually significant.

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